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SY58020U

Micrel, Inc.

M9999-102811

hbwhelp@micrel.com or (408) 955-1690

DESCRIPTION

- Precision 1:4, 400mV CML fanout buffer

- Low jitter performance:

- Guaranteed AC performance over temperature/

voltage:

• < 15ps max. skew

- Accepts an input signal as low as 100mV

DC-coupled and AC-coupled differential

inputs: LVPECL, LVDS, and CML

- 50ohms source terminated CML outputs

- Power supply 2.5V ±5% and 3.3V ±10%

- Industrial temperature range: –40°C to +85°C

- Available in 16-pin (3mm * 3mm) QFN package

FEATURES

6GHz, 1:4 CML FANOUT

BUFFER/TRANSLATOR WITH

INTERNAL I/O TERMINATION

SY58020U

APPLICATIONS

- All SONET and All GigE clock distribution

- Fibre Channel clock and data distribution

- Backplane distribution

- Data distribution: OC-48, OC-48+FEC, XAUI

- High-end, low skew, multiprocessor synchronous

clock distribution

Rev.: C

Amendment: /0

Issue Date: October 2011

The SY58020U is a 2.5V/3.3V precision, high-speed, fully

differential 1:4 CML fanout buffer. Optimized to provide four

identical output copies with less than 15ps of skew and only

signals as fast as 6GHz.

The differential input includes Micrel’s unique, 3-pin input

termination architecture interfaces to differential LVPECL,

LVDS, and CML signals (AC- or DC-coupled) as small as

100mV without any level-shifting or termination resistor

networks in the signal path. For AC-coupled input interface

to drive 400mV typical swing into 50ohms loads, with

extremely fast rise/fall times guaranteed to be under 60ps.

The SY58020U operates from a 2.5V ±5% supply or

3.3V ±10% supply and is guaranteed over the full industrial

temperature range (–40°C to +85°C). For applications that

require LVPECL outputs, consider the SY58021U or

SY58022U 1:4 fanout buffer with 800mV and 400mV output

swing, respectively. The SY58020U is part of Micrel’s high-

support documentation can be found on Micrel’s web site at

www.micrel.com.

Precision Edge is a registered trademark of Micrel, Inc.

FUNCTIONAL BLOCK DIAGRAM

TYPICAL PERFORMANCE

IN

/IN

Q1

/Q1

Q0

/Q0

50

Ω

50

Ω

Q3

/Q3

Q2

/Q2

2GHz Output

TIME (70ps/div.)